A running control device for a vehicle, in which constant speed running is possible, performs constant speed running control (hereinafter referred to as cruise control) by comparing the actual vehicle speed with a target vehicle speed set by the driver and adjusting acceleration and deceleration of the vehicle such that the actual vehicle speed corresponds with the target vehicle speed.
Also, the running control device for a vehicle described in, for example, Patent Document 1 described below can carry out the cruise control by a normal mode and the cruise control by a fuel-efficient mode in which fuel efficiency is improved more than in the normal mode. In this running control device for a vehicle, the upper limit value of the number of engine rotations in the fuel-efficient mode and the upper limit value of the number of engine rotations in the normal mode are different from each other.